diff --git a/src/compiler/compile/css/Selector.ts b/src/compiler/compile/css/Selector.ts
index bb4a29ebe3..005e5320fd 100644
--- a/src/compiler/compile/css/Selector.ts
+++ b/src/compiler/compile/css/Selector.ts
@@ -61,7 +61,10 @@ export default class Selector {
 			let i = block.selectors.length;
 			while (i--) {
 				const selector = block.selectors[i];
-				if (selector.type === 'PseudoElementSelector' || selector.type === 'PseudoClassSelector') continue;
+				if (selector.type === 'PseudoElementSelector' || selector.type === 'PseudoClassSelector') {
+					if (i === 0) code.prependRight(selector.start, attr);
+					continue;
+				}
 
 				if (selector.type === 'TypeSelector' && selector.name === '*') {
 					code.overwrite(selector.start, selector.end, attr);
diff --git a/test/css/samples/not-selector/expected.css b/test/css/samples/not-selector/expected.css
new file mode 100644
index 0000000000..83a819a9e0
--- /dev/null
+++ b/test/css/samples/not-selector/expected.css
@@ -0,0 +1 @@
+.svelte-xyz:not(.foo){color:red}
\ No newline at end of file
diff --git a/test/css/samples/not-selector/input.svelte b/test/css/samples/not-selector/input.svelte
new file mode 100644
index 0000000000..31a880f2bb
--- /dev/null
+++ b/test/css/samples/not-selector/input.svelte
@@ -0,0 +1,8 @@
+<p class="foo">foo</p>
+<p class="bar">bar</p>
+
+<style>
+	:not(.foo) {
+		color: red;
+	}
+</style>
\ No newline at end of file